An independent committee of experts that advises the Centers for Disease Control and Prevention meeting on Thursday unanimously recommended extra doses of the Moderna and Johnson & Johnson coronavirus vaccines for tens of millions of Americans.
The panel also endorsed the so-called mix-and-match strategy — whether people fully immunized with one company’s vaccine should be allowed to switch to a different one for their booster. Limited evidence strongly suggests that booster doses of one of the two mRNA vaccines — Moderna or Pfizer-BioNTech — more effectively raise antibody levels than a booster dose of the Johnson & Johnson vaccine, the committee noted.
On Wednesday, the Food and Drug Administration authorized all three approaches, signing off on boosters for many Americans who got the Moderna or Johnson & Johnson vaccines, just as it did last month for Pfizer-BioNTech recipients. The F.D.A. also gave its blessing to allowing people eligible for boosters to get the extra dose of a different brand from the one they originally received.
But that decision was not the end of the regulatory road. The C.D.C. and individual states still have roles to play. In practice, who will get the shots and when depends to a great degree on the C.D.C.’s final guidance. The agency’s recommendations do not bind state and local officials, but they hold great sway in the medical community and serve as a blueprint for policymakers across the country.
Here are the next steps:
The panel that met on Thursday was the Advisory Committee on Immunization Practices. It is made up of independent experts that advise the agency on scientific questions, and even though its recommendations are not final, the agency often follows them.
Now that the panel has made its recommendations, the C.D.C.’s director, Dr. Rochelle P. Walensky, will issue guidance that will influence the actions of states, hospitals, pharmacies and other entities that distribute the vaccines.
Last month, Dr. Walensky broke from the panel’s advice when she decided that frontline workers should receive booster shots of the Pfizer-BioNTech vaccine. Such instances are rare, however.
Once the C.D.C. issues its guidance, the baton is passed to state health authorities. Health agencies in the states usually follow the C.D.C.’s advice, and real-world action can be swift. After the agency ruled on the Pfizer boosters, the shots began to be administered that day.